Richard Dix is visionary engineer "Richard McAllan" who manages to convince a group of investors to support his plans for a transatlantic tunnel linking the UK and the USA. Immediately, all of my claustrophobic genes kicked in - that's about 4,000 miles of reinforced concrete at an average depth of 11,000 feet - no, I'd sooner embark of a flying tube travelling 35,000 feet in the air at 700 mph! Anyway, what follows is a clever piece of industrial leisure de main, amidst an environment of dealing and double-dealing; betrayal - and, of course - the obligatory romances (Madge Evans and Helen Vins...